1 /* SCTP kernel implementation
2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001 Intel Corp.
6 * Copyright (c) 2001 La Monte H.P. Yarroll
8 * This file is part of the SCTP kernel implementation
10 * This module provides the abstraction for an SCTP association.
12 * This SCTP implementation is free software;
13 * you can redistribute it and/or modify it under the terms of
14 * the GNU General Public License as published by
15 * the Free Software Foundation; either version 2, or (at your option)
18 * This SCTP implementation is distributed in the hope that it
19 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
20 * ************************
21 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
22 * See the GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with GNU CC; see the file COPYING. If not, write to
26 * the Free Software Foundation, 59 Temple Place - Suite 330,
27 * Boston, MA 02111-1307, USA.
29 * Please send any bug reports or fixes you make to the
31 * lksctp developers <lksctp-developers@lists.sourceforge.net>
33 * Or submit a bug report through the following website:
34 * http://www.sf.net/projects/lksctp
36 * Written or modified by:
37 * La Monte H.P. Yarroll <piggy@acm.org>
38 * Karl Knutson <karl@athena.chicago.il.us>
39 * Jon Grimm <jgrimm@us.ibm.com>
40 * Xingang Guo <xingang.guo@intel.com>
41 * Hui Huang <hui.huang@nokia.com>
42 * Sridhar Samudrala <sri@us.ibm.com>
43 * Daisy Chang <daisyc@us.ibm.com>
44 * Ryan Layer <rmlayer@us.ibm.com>
45 * Kevin Gao <kevin.gao@intel.com>
47 * Any bugs reported given to us we will try to fix... any fixes shared will
48 * be incorporated into the next SCTP release.
51 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
53 #include <linux/types.h>
54 #include <linux/fcntl.h>
55 #include <linux/poll.h>
56 #include <linux/init.h>
58 #include <linux/slab.h>
61 #include <net/sctp/sctp.h>
62 #include <net/sctp/sm.h>
64 /* Forward declarations for internal functions. */
65 static void sctp_assoc_bh_rcv(struct work_struct
*work
);
66 static void sctp_assoc_free_asconf_acks(struct sctp_association
*asoc
);
67 static void sctp_assoc_free_asconf_queue(struct sctp_association
*asoc
);
69 /* Keep track of the new idr low so that we don't re-use association id
70 * numbers too fast. It is protected by they idr spin lock is in the
71 * range of 1 - INT_MAX.
73 static u32 idr_low
= 1;
76 /* 1st Level Abstractions. */
78 /* Initialize a new association from provided memory. */
79 static struct sctp_association
*sctp_association_init(struct sctp_association
*asoc
,
80 const struct sctp_endpoint
*ep
,
81 const struct sock
*sk
,
85 struct net
*net
= sock_net(sk
);
91 /* Retrieve the SCTP per socket area. */
92 sp
= sctp_sk((struct sock
*)sk
);
94 /* Discarding const is appropriate here. */
95 asoc
->ep
= (struct sctp_endpoint
*)ep
;
96 sctp_endpoint_hold(asoc
->ep
);
99 asoc
->base
.sk
= (struct sock
*)sk
;
100 sock_hold(asoc
->base
.sk
);
102 /* Initialize the common base substructure. */
103 asoc
->base
.type
= SCTP_EP_TYPE_ASSOCIATION
;
105 /* Initialize the object handling fields. */
106 atomic_set(&asoc
->base
.refcnt
, 1);
108 asoc
->base
.malloced
= 0;
110 /* Initialize the bind addr area. */
111 sctp_bind_addr_init(&asoc
->base
.bind_addr
, ep
->base
.bind_addr
.port
);
113 asoc
->state
= SCTP_STATE_CLOSED
;
115 /* Set these values from the socket values, a conversion between
116 * millsecons to seconds/microseconds must also be done.
118 asoc
->cookie_life
.tv_sec
= sp
->assocparams
.sasoc_cookie_life
/ 1000;
119 asoc
->cookie_life
.tv_usec
= (sp
->assocparams
.sasoc_cookie_life
% 1000)
121 asoc
->frag_point
= 0;
122 asoc
->user_frag
= sp
->user_frag
;
124 /* Set the association max_retrans and RTO values from the
127 asoc
->max_retrans
= sp
->assocparams
.sasoc_asocmaxrxt
;
128 asoc
->pf_retrans
= net
->sctp
.pf_retrans
;
130 asoc
->rto_initial
= msecs_to_jiffies(sp
->rtoinfo
.srto_initial
);
131 asoc
->rto_max
= msecs_to_jiffies(sp
->rtoinfo
.srto_max
);
132 asoc
->rto_min
= msecs_to_jiffies(sp
->rtoinfo
.srto_min
);
134 asoc
->overall_error_count
= 0;
136 /* Initialize the association's heartbeat interval based on the
137 * sock configured value.
139 asoc
->hbinterval
= msecs_to_jiffies(sp
->hbinterval
);
141 /* Initialize path max retrans value. */
142 asoc
->pathmaxrxt
= sp
->pathmaxrxt
;
144 /* Initialize default path MTU. */
145 asoc
->pathmtu
= sp
->pathmtu
;
147 /* Set association default SACK delay */
148 asoc
->sackdelay
= msecs_to_jiffies(sp
->sackdelay
);
149 asoc
->sackfreq
= sp
->sackfreq
;
151 /* Set the association default flags controlling
152 * Heartbeat, SACK delay, and Path MTU Discovery.
154 asoc
->param_flags
= sp
->param_flags
;
156 /* Initialize the maximum mumber of new data packets that can be sent
159 asoc
->max_burst
= sp
->max_burst
;
161 /* initialize association timers */
162 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_NONE
] = 0;
163 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T1_COOKIE
] = asoc
->rto_initial
;
164 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T1_INIT
] = asoc
->rto_initial
;
165 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN
] = asoc
->rto_initial
;
166 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T3_RTX
] = 0;
167 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T4_RTO
] = 0;
169 /* sctpimpguide Section 2.12.2
170 * If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the
171 * recommended value of 5 times 'RTO.Max'.
173 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD
]
176 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_HEARTBEAT
] = 0;
177 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_SACK
] = asoc
->sackdelay
;
178 asoc
->timeouts
[SCTP_EVENT_TIMEOUT_AUTOCLOSE
] =
179 min_t(unsigned long, sp
->autoclose
, net
->sctp
.max_autoclose
) * HZ
;
181 /* Initializes the timers */
182 for (i
= SCTP_EVENT_TIMEOUT_NONE
; i
< SCTP_NUM_TIMEOUT_TYPES
; ++i
)
183 setup_timer(&asoc
->timers
[i
], sctp_timer_events
[i
],
184 (unsigned long)asoc
);
186 /* Pull default initialization values from the sock options.
187 * Note: This assumes that the values have already been
188 * validated in the sock.
190 asoc
->c
.sinit_max_instreams
= sp
->initmsg
.sinit_max_instreams
;
191 asoc
->c
.sinit_num_ostreams
= sp
->initmsg
.sinit_num_ostreams
;
192 asoc
->max_init_attempts
= sp
->initmsg
.sinit_max_attempts
;
194 asoc
->max_init_timeo
=
195 msecs_to_jiffies(sp
->initmsg
.sinit_max_init_timeo
);
197 /* Allocate storage for the ssnmap after the inbound and outbound
198 * streams have been negotiated during Init.
202 /* Set the local window size for receive.
203 * This is also the rcvbuf space per association.
204 * RFC 6 - A SCTP receiver MUST be able to receive a minimum of
205 * 1500 bytes in one SCTP packet.
207 if ((sk
->sk_rcvbuf
/2) < SCTP_DEFAULT_MINWINDOW
)
208 asoc
->rwnd
= SCTP_DEFAULT_MINWINDOW
;
210 asoc
->rwnd
= sk
->sk_rcvbuf
/2;
212 asoc
->a_rwnd
= asoc
->rwnd
;
215 asoc
->rwnd_press
= 0;
217 /* Use my own max window until I learn something better. */
218 asoc
->peer
.rwnd
= SCTP_DEFAULT_MAXWINDOW
;
220 /* Set the sndbuf size for transmit. */
221 asoc
->sndbuf_used
= 0;
223 /* Initialize the receive memory counter */
224 atomic_set(&asoc
->rmem_alloc
, 0);
226 init_waitqueue_head(&asoc
->wait
);
228 asoc
->c
.my_vtag
= sctp_generate_tag(ep
);
229 asoc
->peer
.i
.init_tag
= 0; /* INIT needs a vtag of 0. */
230 asoc
->c
.peer_vtag
= 0;
232 asoc
->c
.peer_ttag
= 0;
233 asoc
->c
.my_port
= ep
->base
.bind_addr
.port
;
235 asoc
->c
.initial_tsn
= sctp_generate_tsn(ep
);
237 asoc
->next_tsn
= asoc
->c
.initial_tsn
;
239 asoc
->ctsn_ack_point
= asoc
->next_tsn
- 1;
240 asoc
->adv_peer_ack_point
= asoc
->ctsn_ack_point
;
241 asoc
->highest_sacked
= asoc
->ctsn_ack_point
;
242 asoc
->last_cwr_tsn
= asoc
->ctsn_ack_point
;
243 asoc
->unack_data
= 0;
245 /* ADDIP Section 4.1 Asconf Chunk Procedures
247 * When an endpoint has an ASCONF signaled change to be sent to the
248 * remote endpoint it should do the following:
250 * A2) a serial number should be assigned to the chunk. The serial
251 * number SHOULD be a monotonically increasing number. The serial
252 * numbers SHOULD be initialized at the start of the
253 * association to the same value as the initial TSN.
255 asoc
->addip_serial
= asoc
->c
.initial_tsn
;
257 INIT_LIST_HEAD(&asoc
->addip_chunk_list
);
258 INIT_LIST_HEAD(&asoc
->asconf_ack_list
);
260 /* Make an empty list of remote transport addresses. */
261 INIT_LIST_HEAD(&asoc
->peer
.transport_addr_list
);
262 asoc
->peer
.transport_count
= 0;
264 /* RFC 2960 5.1 Normal Establishment of an Association
266 * After the reception of the first data chunk in an
267 * association the endpoint must immediately respond with a
268 * sack to acknowledge the data chunk. Subsequent
269 * acknowledgements should be done as described in Section
272 * [We implement this by telling a new association that it
273 * already received one packet.]
275 asoc
->peer
.sack_needed
= 1;
276 asoc
->peer
.sack_cnt
= 0;
277 asoc
->peer
.sack_generation
= 1;
279 /* Assume that the peer will tell us if he recognizes ASCONF
280 * as part of INIT exchange.
281 * The sctp_addip_noauth option is there for backward compatibilty
282 * and will revert old behavior.
284 asoc
->peer
.asconf_capable
= 0;
285 if (net
->sctp
.addip_noauth
)
286 asoc
->peer
.asconf_capable
= 1;
287 asoc
->asconf_addr_del_pending
= NULL
;
288 asoc
->src_out_of_asoc_ok
= 0;
289 asoc
->new_transport
= NULL
;
291 /* Create an input queue. */
292 sctp_inq_init(&asoc
->base
.inqueue
);
293 sctp_inq_set_th_handler(&asoc
->base
.inqueue
, sctp_assoc_bh_rcv
);
295 /* Create an output queue. */
296 sctp_outq_init(asoc
, &asoc
->outqueue
);
298 if (!sctp_ulpq_init(&asoc
->ulpq
, asoc
))
301 memset(&asoc
->peer
.tsn_map
, 0, sizeof(struct sctp_tsnmap
));
307 /* Assume that peer would support both address types unless we are
310 asoc
->peer
.ipv4_address
= 1;
311 if (asoc
->base
.sk
->sk_family
== PF_INET6
)
312 asoc
->peer
.ipv6_address
= 1;
313 INIT_LIST_HEAD(&asoc
->asocs
);
315 asoc
->autoclose
= sp
->autoclose
;
317 asoc
->default_stream
= sp
->default_stream
;
318 asoc
->default_ppid
= sp
->default_ppid
;
319 asoc
->default_flags
= sp
->default_flags
;
320 asoc
->default_context
= sp
->default_context
;
321 asoc
->default_timetolive
= sp
->default_timetolive
;
322 asoc
->default_rcv_context
= sp
->default_rcv_context
;
324 /* SCTP_GET_ASSOC_STATS COUNTERS */
325 memset(&asoc
->stats
, 0, sizeof(struct sctp_priv_assoc_stats
));
327 /* AUTH related initializations */
328 INIT_LIST_HEAD(&asoc
->endpoint_shared_keys
);
329 err
= sctp_auth_asoc_copy_shkeys(ep
, asoc
, gfp
);
333 asoc
->active_key_id
= ep
->active_key_id
;
334 asoc
->asoc_shared_key
= NULL
;
336 asoc
->default_hmac_id
= 0;
337 /* Save the hmacs and chunks list into this association */
338 if (ep
->auth_hmacs_list
)
339 memcpy(asoc
->c
.auth_hmacs
, ep
->auth_hmacs_list
,
340 ntohs(ep
->auth_hmacs_list
->param_hdr
.length
));
341 if (ep
->auth_chunk_list
)
342 memcpy(asoc
->c
.auth_chunks
, ep
->auth_chunk_list
,
343 ntohs(ep
->auth_chunk_list
->param_hdr
.length
));
345 /* Get the AUTH random number for this association */
346 p
= (sctp_paramhdr_t
*)asoc
->c
.auth_random
;
347 p
->type
= SCTP_PARAM_RANDOM
;
348 p
->length
= htons(sizeof(sctp_paramhdr_t
) + SCTP_AUTH_RANDOM_LENGTH
);
349 get_random_bytes(p
+1, SCTP_AUTH_RANDOM_LENGTH
);
354 sctp_endpoint_put(asoc
->ep
);
355 sock_put(asoc
->base
.sk
);
359 /* Allocate and initialize a new association */
360 struct sctp_association
*sctp_association_new(const struct sctp_endpoint
*ep
,
361 const struct sock
*sk
,
365 struct sctp_association
*asoc
;
367 asoc
= t_new(struct sctp_association
, gfp
);
371 if (!sctp_association_init(asoc
, ep
, sk
, scope
, gfp
))
374 asoc
->base
.malloced
= 1;
375 SCTP_DBG_OBJCNT_INC(assoc
);
376 SCTP_DEBUG_PRINTK("Created asoc %p\n", asoc
);
386 /* Free this association if possible. There may still be users, so
387 * the actual deallocation may be delayed.
389 void sctp_association_free(struct sctp_association
*asoc
)
391 struct sock
*sk
= asoc
->base
.sk
;
392 struct sctp_transport
*transport
;
393 struct list_head
*pos
, *temp
;
396 /* Only real associations count against the endpoint, so
397 * don't bother for if this is a temporary association.
400 list_del(&asoc
->asocs
);
402 /* Decrement the backlog value for a TCP-style listening
405 if (sctp_style(sk
, TCP
) && sctp_sstate(sk
, LISTENING
))
406 sk
->sk_ack_backlog
--;
409 /* Mark as dead, so other users can know this structure is
414 /* Dispose of any data lying around in the outqueue. */
415 sctp_outq_free(&asoc
->outqueue
);
417 /* Dispose of any pending messages for the upper layer. */
418 sctp_ulpq_free(&asoc
->ulpq
);
420 /* Dispose of any pending chunks on the inqueue. */
421 sctp_inq_free(&asoc
->base
.inqueue
);
423 sctp_tsnmap_free(&asoc
->peer
.tsn_map
);
425 /* Free ssnmap storage. */
426 sctp_ssnmap_free(asoc
->ssnmap
);
428 /* Clean up the bound address list. */
429 sctp_bind_addr_free(&asoc
->base
.bind_addr
);
431 /* Do we need to go through all of our timers and
432 * delete them? To be safe we will try to delete all, but we
433 * should be able to go through and make a guess based
436 for (i
= SCTP_EVENT_TIMEOUT_NONE
; i
< SCTP_NUM_TIMEOUT_TYPES
; ++i
) {
437 if (del_timer(&asoc
->timers
[i
]))
438 sctp_association_put(asoc
);
441 /* Free peer's cached cookie. */
442 kfree(asoc
->peer
.cookie
);
443 kfree(asoc
->peer
.peer_random
);
444 kfree(asoc
->peer
.peer_chunks
);
445 kfree(asoc
->peer
.peer_hmacs
);
447 /* Release the transport structures. */
448 list_for_each_safe(pos
, temp
, &asoc
->peer
.transport_addr_list
) {
449 transport
= list_entry(pos
, struct sctp_transport
, transports
);
451 sctp_transport_free(transport
);
454 asoc
->peer
.transport_count
= 0;
456 sctp_asconf_queue_teardown(asoc
);
458 /* Free pending address space being deleted */
459 if (asoc
->asconf_addr_del_pending
!= NULL
)
460 kfree(asoc
->asconf_addr_del_pending
);
462 /* AUTH - Free the endpoint shared keys */
463 sctp_auth_destroy_keys(&asoc
->endpoint_shared_keys
);
465 /* AUTH - Free the association shared key */
466 sctp_auth_key_put(asoc
->asoc_shared_key
);
468 sctp_association_put(asoc
);
471 /* Cleanup and free up an association. */
472 static void sctp_association_destroy(struct sctp_association
*asoc
)
474 SCTP_ASSERT(asoc
->base
.dead
, "Assoc is not dead", return);
476 sctp_endpoint_put(asoc
->ep
);
477 sock_put(asoc
->base
.sk
);
479 if (asoc
->assoc_id
!= 0) {
480 spin_lock_bh(&sctp_assocs_id_lock
);
481 idr_remove(&sctp_assocs_id
, asoc
->assoc_id
);
482 spin_unlock_bh(&sctp_assocs_id_lock
);
485 WARN_ON(atomic_read(&asoc
->rmem_alloc
));
487 if (asoc
->base
.malloced
) {
489 SCTP_DBG_OBJCNT_DEC(assoc
);
493 /* Change the primary destination address for the peer. */
494 void sctp_assoc_set_primary(struct sctp_association
*asoc
,
495 struct sctp_transport
*transport
)
499 /* it's a changeover only if we already have a primary path
500 * that we are changing
502 if (asoc
->peer
.primary_path
!= NULL
&&
503 asoc
->peer
.primary_path
!= transport
)
506 asoc
->peer
.primary_path
= transport
;
508 /* Set a default msg_name for events. */
509 memcpy(&asoc
->peer
.primary_addr
, &transport
->ipaddr
,
510 sizeof(union sctp_addr
));
512 /* If the primary path is changing, assume that the
513 * user wants to use this new path.
515 if ((transport
->state
== SCTP_ACTIVE
) ||
516 (transport
->state
== SCTP_UNKNOWN
))
517 asoc
->peer
.active_path
= transport
;
520 * SFR-CACC algorithm:
521 * Upon the receipt of a request to change the primary
522 * destination address, on the data structure for the new
523 * primary destination, the sender MUST do the following:
525 * 1) If CHANGEOVER_ACTIVE is set, then there was a switch
526 * to this destination address earlier. The sender MUST set
527 * CYCLING_CHANGEOVER to indicate that this switch is a
528 * double switch to the same destination address.
530 * Really, only bother is we have data queued or outstanding on
533 if (!asoc
->outqueue
.outstanding_bytes
&& !asoc
->outqueue
.out_qlen
)
536 if (transport
->cacc
.changeover_active
)
537 transport
->cacc
.cycling_changeover
= changeover
;
539 /* 2) The sender MUST set CHANGEOVER_ACTIVE to indicate that
540 * a changeover has occurred.
542 transport
->cacc
.changeover_active
= changeover
;
544 /* 3) The sender MUST store the next TSN to be sent in
545 * next_tsn_at_change.
547 transport
->cacc
.next_tsn_at_change
= asoc
->next_tsn
;
550 /* Remove a transport from an association. */
551 void sctp_assoc_rm_peer(struct sctp_association
*asoc
,
552 struct sctp_transport
*peer
)
554 struct list_head
*pos
;
555 struct sctp_transport
*transport
;
557 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_rm_peer:association %p addr: ",
561 ntohs(peer
->ipaddr
.v4
.sin_port
));
563 /* If we are to remove the current retran_path, update it
564 * to the next peer before removing this peer from the list.
566 if (asoc
->peer
.retran_path
== peer
)
567 sctp_assoc_update_retran_path(asoc
);
569 /* Remove this peer from the list. */
570 list_del_rcu(&peer
->transports
);
572 /* Get the first transport of asoc. */
573 pos
= asoc
->peer
.transport_addr_list
.next
;
574 transport
= list_entry(pos
, struct sctp_transport
, transports
);
576 /* Update any entries that match the peer to be deleted. */
577 if (asoc
->peer
.primary_path
== peer
)
578 sctp_assoc_set_primary(asoc
, transport
);
579 if (asoc
->peer
.active_path
== peer
)
580 asoc
->peer
.active_path
= transport
;
581 if (asoc
->peer
.retran_path
== peer
)
582 asoc
->peer
.retran_path
= transport
;
583 if (asoc
->peer
.last_data_from
== peer
)
584 asoc
->peer
.last_data_from
= transport
;
586 /* If we remove the transport an INIT was last sent to, set it to
587 * NULL. Combined with the update of the retran path above, this
588 * will cause the next INIT to be sent to the next available
589 * transport, maintaining the cycle.
591 if (asoc
->init_last_sent_to
== peer
)
592 asoc
->init_last_sent_to
= NULL
;
594 /* If we remove the transport an SHUTDOWN was last sent to, set it
595 * to NULL. Combined with the update of the retran path above, this
596 * will cause the next SHUTDOWN to be sent to the next available
597 * transport, maintaining the cycle.
599 if (asoc
->shutdown_last_sent_to
== peer
)
600 asoc
->shutdown_last_sent_to
= NULL
;
602 /* If we remove the transport an ASCONF was last sent to, set it to
605 if (asoc
->addip_last_asconf
&&
606 asoc
->addip_last_asconf
->transport
== peer
)
607 asoc
->addip_last_asconf
->transport
= NULL
;
609 /* If we have something on the transmitted list, we have to
610 * save it off. The best place is the active path.
612 if (!list_empty(&peer
->transmitted
)) {
613 struct sctp_transport
*active
= asoc
->peer
.active_path
;
614 struct sctp_chunk
*ch
;
616 /* Reset the transport of each chunk on this list */
617 list_for_each_entry(ch
, &peer
->transmitted
,
619 ch
->transport
= NULL
;
620 ch
->rtt_in_progress
= 0;
623 list_splice_tail_init(&peer
->transmitted
,
624 &active
->transmitted
);
626 /* Start a T3 timer here in case it wasn't running so
627 * that these migrated packets have a chance to get
630 if (!timer_pending(&active
->T3_rtx_timer
))
631 if (!mod_timer(&active
->T3_rtx_timer
,
632 jiffies
+ active
->rto
))
633 sctp_transport_hold(active
);
636 asoc
->peer
.transport_count
--;
638 sctp_transport_free(peer
);
641 /* Add a transport address to an association. */
642 struct sctp_transport
*sctp_assoc_add_peer(struct sctp_association
*asoc
,
643 const union sctp_addr
*addr
,
645 const int peer_state
)
647 struct net
*net
= sock_net(asoc
->base
.sk
);
648 struct sctp_transport
*peer
;
649 struct sctp_sock
*sp
;
652 sp
= sctp_sk(asoc
->base
.sk
);
654 /* AF_INET and AF_INET6 share common port field. */
655 port
= ntohs(addr
->v4
.sin_port
);
657 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_add_peer:association %p addr: ",
658 " port: %d state:%d\n",
664 /* Set the port if it has not been set yet. */
665 if (0 == asoc
->peer
.port
)
666 asoc
->peer
.port
= port
;
668 /* Check to see if this is a duplicate. */
669 peer
= sctp_assoc_lookup_paddr(asoc
, addr
);
671 /* An UNKNOWN state is only set on transports added by
672 * user in sctp_connectx() call. Such transports should be
673 * considered CONFIRMED per RFC 4960, Section 5.4.
675 if (peer
->state
== SCTP_UNKNOWN
) {
676 peer
->state
= SCTP_ACTIVE
;
681 peer
= sctp_transport_new(net
, addr
, gfp
);
685 sctp_transport_set_owner(peer
, asoc
);
687 /* Initialize the peer's heartbeat interval based on the
688 * association configured value.
690 peer
->hbinterval
= asoc
->hbinterval
;
692 /* Set the path max_retrans. */
693 peer
->pathmaxrxt
= asoc
->pathmaxrxt
;
695 /* And the partial failure retrnas threshold */
696 peer
->pf_retrans
= asoc
->pf_retrans
;
698 /* Initialize the peer's SACK delay timeout based on the
699 * association configured value.
701 peer
->sackdelay
= asoc
->sackdelay
;
702 peer
->sackfreq
= asoc
->sackfreq
;
704 /* Enable/disable heartbeat, SACK delay, and path MTU discovery
705 * based on association setting.
707 peer
->param_flags
= asoc
->param_flags
;
709 sctp_transport_route(peer
, NULL
, sp
);
711 /* Initialize the pmtu of the transport. */
712 if (peer
->param_flags
& SPP_PMTUD_DISABLE
) {
714 peer
->pathmtu
= asoc
->pathmtu
;
716 peer
->pathmtu
= SCTP_DEFAULT_MAXSEGMENT
;
719 /* If this is the first transport addr on this association,
720 * initialize the association PMTU to the peer's PMTU.
721 * If not and the current association PMTU is higher than the new
722 * peer's PMTU, reset the association PMTU to the new peer's PMTU.
725 asoc
->pathmtu
= min_t(int, peer
->pathmtu
, asoc
->pathmtu
);
727 asoc
->pathmtu
= peer
->pathmtu
;
729 SCTP_DEBUG_PRINTK("sctp_assoc_add_peer:association %p PMTU set to "
730 "%d\n", asoc
, asoc
->pathmtu
);
731 peer
->pmtu_pending
= 0;
733 asoc
->frag_point
= sctp_frag_point(asoc
, asoc
->pathmtu
);
735 /* The asoc->peer.port might not be meaningful yet, but
736 * initialize the packet structure anyway.
738 sctp_packet_init(&peer
->packet
, peer
, asoc
->base
.bind_addr
.port
,
743 * o The initial cwnd before DATA transmission or after a sufficiently
744 * long idle period MUST be set to
745 * min(4*MTU, max(2*MTU, 4380 bytes))
747 * o The initial value of ssthresh MAY be arbitrarily high
748 * (for example, implementations MAY use the size of the
749 * receiver advertised window).
751 peer
->cwnd
= min(4*asoc
->pathmtu
, max_t(__u32
, 2*asoc
->pathmtu
, 4380));
753 /* At this point, we may not have the receiver's advertised window,
754 * so initialize ssthresh to the default value and it will be set
755 * later when we process the INIT.
757 peer
->ssthresh
= SCTP_DEFAULT_MAXWINDOW
;
759 peer
->partial_bytes_acked
= 0;
760 peer
->flight_size
= 0;
761 peer
->burst_limited
= 0;
763 /* Set the transport's RTO.initial value */
764 peer
->rto
= asoc
->rto_initial
;
765 sctp_max_rto(asoc
, peer
);
767 /* Set the peer's active state. */
768 peer
->state
= peer_state
;
770 /* Attach the remote transport to our asoc. */
771 list_add_tail_rcu(&peer
->transports
, &asoc
->peer
.transport_addr_list
);
772 asoc
->peer
.transport_count
++;
774 /* If we do not yet have a primary path, set one. */
775 if (!asoc
->peer
.primary_path
) {
776 sctp_assoc_set_primary(asoc
, peer
);
777 asoc
->peer
.retran_path
= peer
;
780 if (asoc
->peer
.active_path
== asoc
->peer
.retran_path
&&
781 peer
->state
!= SCTP_UNCONFIRMED
) {
782 asoc
->peer
.retran_path
= peer
;
788 /* Delete a transport address from an association. */
789 void sctp_assoc_del_peer(struct sctp_association
*asoc
,
790 const union sctp_addr
*addr
)
792 struct list_head
*pos
;
793 struct list_head
*temp
;
794 struct sctp_transport
*transport
;
796 list_for_each_safe(pos
, temp
, &asoc
->peer
.transport_addr_list
) {
797 transport
= list_entry(pos
, struct sctp_transport
, transports
);
798 if (sctp_cmp_addr_exact(addr
, &transport
->ipaddr
)) {
799 /* Do book keeping for removing the peer and free it. */
800 sctp_assoc_rm_peer(asoc
, transport
);
806 /* Lookup a transport by address. */
807 struct sctp_transport
*sctp_assoc_lookup_paddr(
808 const struct sctp_association
*asoc
,
809 const union sctp_addr
*address
)
811 struct sctp_transport
*t
;
813 /* Cycle through all transports searching for a peer address. */
815 list_for_each_entry(t
, &asoc
->peer
.transport_addr_list
,
817 if (sctp_cmp_addr_exact(address
, &t
->ipaddr
))
824 /* Remove all transports except a give one */
825 void sctp_assoc_del_nonprimary_peers(struct sctp_association
*asoc
,
826 struct sctp_transport
*primary
)
828 struct sctp_transport
*temp
;
829 struct sctp_transport
*t
;
831 list_for_each_entry_safe(t
, temp
, &asoc
->peer
.transport_addr_list
,
833 /* if the current transport is not the primary one, delete it */
835 sctp_assoc_rm_peer(asoc
, t
);
839 /* Engage in transport control operations.
840 * Mark the transport up or down and send a notification to the user.
841 * Select and update the new active and retran paths.
843 void sctp_assoc_control_transport(struct sctp_association
*asoc
,
844 struct sctp_transport
*transport
,
845 sctp_transport_cmd_t command
,
846 sctp_sn_error_t error
)
848 struct sctp_transport
*t
= NULL
;
849 struct sctp_transport
*first
;
850 struct sctp_transport
*second
;
851 struct sctp_ulpevent
*event
;
852 struct sockaddr_storage addr
;
854 bool ulp_notify
= true;
856 /* Record the transition on the transport. */
858 case SCTP_TRANSPORT_UP
:
859 /* If we are moving from UNCONFIRMED state due
860 * to heartbeat success, report the SCTP_ADDR_CONFIRMED
861 * state to the user, otherwise report SCTP_ADDR_AVAILABLE.
863 if (SCTP_UNCONFIRMED
== transport
->state
&&
864 SCTP_HEARTBEAT_SUCCESS
== error
)
865 spc_state
= SCTP_ADDR_CONFIRMED
;
867 spc_state
= SCTP_ADDR_AVAILABLE
;
868 /* Don't inform ULP about transition from PF to
869 * active state and set cwnd to 1, see SCTP
870 * Quick failover draft section 5.1, point 5
872 if (transport
->state
== SCTP_PF
) {
876 transport
->state
= SCTP_ACTIVE
;
879 case SCTP_TRANSPORT_DOWN
:
880 /* If the transport was never confirmed, do not transition it
881 * to inactive state. Also, release the cached route since
882 * there may be a better route next time.
884 if (transport
->state
!= SCTP_UNCONFIRMED
)
885 transport
->state
= SCTP_INACTIVE
;
887 dst_release(transport
->dst
);
888 transport
->dst
= NULL
;
891 spc_state
= SCTP_ADDR_UNREACHABLE
;
894 case SCTP_TRANSPORT_PF
:
895 transport
->state
= SCTP_PF
;
903 /* Generate and send a SCTP_PEER_ADDR_CHANGE notification to the
907 memset(&addr
, 0, sizeof(struct sockaddr_storage
));
908 memcpy(&addr
, &transport
->ipaddr
,
909 transport
->af_specific
->sockaddr_len
);
910 event
= sctp_ulpevent_make_peer_addr_change(asoc
, &addr
,
911 0, spc_state
, error
, GFP_ATOMIC
);
913 sctp_ulpq_tail_event(&asoc
->ulpq
, event
);
916 /* Select new active and retran paths. */
918 /* Look for the two most recently used active transports.
920 * This code produces the wrong ordering whenever jiffies
921 * rolls over, but we still get usable transports, so we don't
924 first
= NULL
; second
= NULL
;
926 list_for_each_entry(t
, &asoc
->peer
.transport_addr_list
,
929 if ((t
->state
== SCTP_INACTIVE
) ||
930 (t
->state
== SCTP_UNCONFIRMED
) ||
931 (t
->state
== SCTP_PF
))
933 if (!first
|| t
->last_time_heard
> first
->last_time_heard
) {
937 if (!second
|| t
->last_time_heard
> second
->last_time_heard
)
941 /* RFC 2960 6.4 Multi-Homed SCTP Endpoints
943 * By default, an endpoint should always transmit to the
944 * primary path, unless the SCTP user explicitly specifies the
945 * destination transport address (and possibly source
946 * transport address) to use.
948 * [If the primary is active but not most recent, bump the most
949 * recently used transport.]
951 if (((asoc
->peer
.primary_path
->state
== SCTP_ACTIVE
) ||
952 (asoc
->peer
.primary_path
->state
== SCTP_UNKNOWN
)) &&
953 first
!= asoc
->peer
.primary_path
) {
955 first
= asoc
->peer
.primary_path
;
958 /* If we failed to find a usable transport, just camp on the
959 * primary, even if it is inactive.
962 first
= asoc
->peer
.primary_path
;
963 second
= asoc
->peer
.primary_path
;
966 /* Set the active and retran transports. */
967 asoc
->peer
.active_path
= first
;
968 asoc
->peer
.retran_path
= second
;
971 /* Hold a reference to an association. */
972 void sctp_association_hold(struct sctp_association
*asoc
)
974 atomic_inc(&asoc
->base
.refcnt
);
977 /* Release a reference to an association and cleanup
978 * if there are no more references.
980 void sctp_association_put(struct sctp_association
*asoc
)
982 if (atomic_dec_and_test(&asoc
->base
.refcnt
))
983 sctp_association_destroy(asoc
);
986 /* Allocate the next TSN, Transmission Sequence Number, for the given
989 __u32
sctp_association_get_next_tsn(struct sctp_association
*asoc
)
991 /* From Section 1.6 Serial Number Arithmetic:
992 * Transmission Sequence Numbers wrap around when they reach
993 * 2**32 - 1. That is, the next TSN a DATA chunk MUST use
994 * after transmitting TSN = 2*32 - 1 is TSN = 0.
996 __u32 retval
= asoc
->next_tsn
;
1003 /* Compare two addresses to see if they match. Wildcard addresses
1004 * only match themselves.
1006 int sctp_cmp_addr_exact(const union sctp_addr
*ss1
,
1007 const union sctp_addr
*ss2
)
1011 af
= sctp_get_af_specific(ss1
->sa
.sa_family
);
1015 return af
->cmp_addr(ss1
, ss2
);
1018 /* Return an ecne chunk to get prepended to a packet.
1019 * Note: We are sly and return a shared, prealloced chunk. FIXME:
1020 * No we don't, but we could/should.
1022 struct sctp_chunk
*sctp_get_ecne_prepend(struct sctp_association
*asoc
)
1024 struct sctp_chunk
*chunk
;
1026 /* Send ECNE if needed.
1027 * Not being able to allocate a chunk here is not deadly.
1029 if (asoc
->need_ecne
)
1030 chunk
= sctp_make_ecne(asoc
, asoc
->last_ecne_tsn
);
1038 * Find which transport this TSN was sent on.
1040 struct sctp_transport
*sctp_assoc_lookup_tsn(struct sctp_association
*asoc
,
1043 struct sctp_transport
*active
;
1044 struct sctp_transport
*match
;
1045 struct sctp_transport
*transport
;
1046 struct sctp_chunk
*chunk
;
1047 __be32 key
= htonl(tsn
);
1052 * FIXME: In general, find a more efficient data structure for
1057 * The general strategy is to search each transport's transmitted
1058 * list. Return which transport this TSN lives on.
1060 * Let's be hopeful and check the active_path first.
1061 * Another optimization would be to know if there is only one
1062 * outbound path and not have to look for the TSN at all.
1066 active
= asoc
->peer
.active_path
;
1068 list_for_each_entry(chunk
, &active
->transmitted
,
1071 if (key
== chunk
->subh
.data_hdr
->tsn
) {
1077 /* If not found, go search all the other transports. */
1078 list_for_each_entry(transport
, &asoc
->peer
.transport_addr_list
,
1081 if (transport
== active
)
1083 list_for_each_entry(chunk
, &transport
->transmitted
,
1085 if (key
== chunk
->subh
.data_hdr
->tsn
) {
1095 /* Is this the association we are looking for? */
1096 struct sctp_transport
*sctp_assoc_is_match(struct sctp_association
*asoc
,
1098 const union sctp_addr
*laddr
,
1099 const union sctp_addr
*paddr
)
1101 struct sctp_transport
*transport
;
1103 if ((htons(asoc
->base
.bind_addr
.port
) == laddr
->v4
.sin_port
) &&
1104 (htons(asoc
->peer
.port
) == paddr
->v4
.sin_port
) &&
1105 net_eq(sock_net(asoc
->base
.sk
), net
)) {
1106 transport
= sctp_assoc_lookup_paddr(asoc
, paddr
);
1110 if (sctp_bind_addr_match(&asoc
->base
.bind_addr
, laddr
,
1111 sctp_sk(asoc
->base
.sk
)))
1120 /* Do delayed input processing. This is scheduled by sctp_rcv(). */
1121 static void sctp_assoc_bh_rcv(struct work_struct
*work
)
1123 struct sctp_association
*asoc
=
1124 container_of(work
, struct sctp_association
,
1125 base
.inqueue
.immediate
);
1126 struct net
*net
= sock_net(asoc
->base
.sk
);
1127 struct sctp_endpoint
*ep
;
1128 struct sctp_chunk
*chunk
;
1129 struct sctp_inq
*inqueue
;
1131 sctp_subtype_t subtype
;
1134 /* The association should be held so we should be safe. */
1137 inqueue
= &asoc
->base
.inqueue
;
1138 sctp_association_hold(asoc
);
1139 while (NULL
!= (chunk
= sctp_inq_pop(inqueue
))) {
1140 state
= asoc
->state
;
1141 subtype
= SCTP_ST_CHUNK(chunk
->chunk_hdr
->type
);
1143 /* SCTP-AUTH, Section 6.3:
1144 * The receiver has a list of chunk types which it expects
1145 * to be received only after an AUTH-chunk. This list has
1146 * been sent to the peer during the association setup. It
1147 * MUST silently discard these chunks if they are not placed
1148 * after an AUTH chunk in the packet.
1150 if (sctp_auth_recv_cid(subtype
.chunk
, asoc
) && !chunk
->auth
)
1153 /* Remember where the last DATA chunk came from so we
1154 * know where to send the SACK.
1156 if (sctp_chunk_is_data(chunk
))
1157 asoc
->peer
.last_data_from
= chunk
->transport
;
1159 SCTP_INC_STATS(net
, SCTP_MIB_INCTRLCHUNKS
);
1160 asoc
->stats
.ictrlchunks
++;
1161 if (chunk
->chunk_hdr
->type
== SCTP_CID_SACK
)
1162 asoc
->stats
.isacks
++;
1165 if (chunk
->transport
)
1166 chunk
->transport
->last_time_heard
= jiffies
;
1168 /* Run through the state machine. */
1169 error
= sctp_do_sm(net
, SCTP_EVENT_T_CHUNK
, subtype
,
1170 state
, ep
, asoc
, chunk
, GFP_ATOMIC
);
1172 /* Check to see if the association is freed in response to
1173 * the incoming chunk. If so, get out of the while loop.
1175 if (asoc
->base
.dead
)
1178 /* If there is an error on chunk, discard this packet. */
1180 chunk
->pdiscard
= 1;
1182 sctp_association_put(asoc
);
1185 /* This routine moves an association from its old sk to a new sk. */
1186 void sctp_assoc_migrate(struct sctp_association
*assoc
, struct sock
*newsk
)
1188 struct sctp_sock
*newsp
= sctp_sk(newsk
);
1189 struct sock
*oldsk
= assoc
->base
.sk
;
1191 /* Delete the association from the old endpoint's list of
1194 list_del_init(&assoc
->asocs
);
1196 /* Decrement the backlog value for a TCP-style socket. */
1197 if (sctp_style(oldsk
, TCP
))
1198 oldsk
->sk_ack_backlog
--;
1200 /* Release references to the old endpoint and the sock. */
1201 sctp_endpoint_put(assoc
->ep
);
1202 sock_put(assoc
->base
.sk
);
1204 /* Get a reference to the new endpoint. */
1205 assoc
->ep
= newsp
->ep
;
1206 sctp_endpoint_hold(assoc
->ep
);
1208 /* Get a reference to the new sock. */
1209 assoc
->base
.sk
= newsk
;
1210 sock_hold(assoc
->base
.sk
);
1212 /* Add the association to the new endpoint's list of associations. */
1213 sctp_endpoint_add_asoc(newsp
->ep
, assoc
);
1216 /* Update an association (possibly from unexpected COOKIE-ECHO processing). */
1217 void sctp_assoc_update(struct sctp_association
*asoc
,
1218 struct sctp_association
*new)
1220 struct sctp_transport
*trans
;
1221 struct list_head
*pos
, *temp
;
1223 /* Copy in new parameters of peer. */
1225 asoc
->peer
.rwnd
= new->peer
.rwnd
;
1226 asoc
->peer
.sack_needed
= new->peer
.sack_needed
;
1227 asoc
->peer
.i
= new->peer
.i
;
1228 sctp_tsnmap_init(&asoc
->peer
.tsn_map
, SCTP_TSN_MAP_INITIAL
,
1229 asoc
->peer
.i
.initial_tsn
, GFP_ATOMIC
);
1231 /* Remove any peer addresses not present in the new association. */
1232 list_for_each_safe(pos
, temp
, &asoc
->peer
.transport_addr_list
) {
1233 trans
= list_entry(pos
, struct sctp_transport
, transports
);
1234 if (!sctp_assoc_lookup_paddr(new, &trans
->ipaddr
)) {
1235 sctp_assoc_rm_peer(asoc
, trans
);
1239 if (asoc
->state
>= SCTP_STATE_ESTABLISHED
)
1240 sctp_transport_reset(trans
);
1243 /* If the case is A (association restart), use
1244 * initial_tsn as next_tsn. If the case is B, use
1245 * current next_tsn in case data sent to peer
1246 * has been discarded and needs retransmission.
1248 if (asoc
->state
>= SCTP_STATE_ESTABLISHED
) {
1249 asoc
->next_tsn
= new->next_tsn
;
1250 asoc
->ctsn_ack_point
= new->ctsn_ack_point
;
1251 asoc
->adv_peer_ack_point
= new->adv_peer_ack_point
;
1253 /* Reinitialize SSN for both local streams
1254 * and peer's streams.
1256 sctp_ssnmap_clear(asoc
->ssnmap
);
1258 /* Flush the ULP reassembly and ordered queue.
1259 * Any data there will now be stale and will
1262 sctp_ulpq_flush(&asoc
->ulpq
);
1264 /* reset the overall association error count so
1265 * that the restarted association doesn't get torn
1266 * down on the next retransmission timer.
1268 asoc
->overall_error_count
= 0;
1271 /* Add any peer addresses from the new association. */
1272 list_for_each_entry(trans
, &new->peer
.transport_addr_list
,
1274 if (!sctp_assoc_lookup_paddr(asoc
, &trans
->ipaddr
))
1275 sctp_assoc_add_peer(asoc
, &trans
->ipaddr
,
1276 GFP_ATOMIC
, trans
->state
);
1279 asoc
->ctsn_ack_point
= asoc
->next_tsn
- 1;
1280 asoc
->adv_peer_ack_point
= asoc
->ctsn_ack_point
;
1281 if (!asoc
->ssnmap
) {
1282 /* Move the ssnmap. */
1283 asoc
->ssnmap
= new->ssnmap
;
1287 if (!asoc
->assoc_id
) {
1288 /* get a new association id since we don't have one
1291 sctp_assoc_set_id(asoc
, GFP_ATOMIC
);
1295 /* SCTP-AUTH: Save the peer parameters from the new assocaitions
1296 * and also move the association shared keys over
1298 kfree(asoc
->peer
.peer_random
);
1299 asoc
->peer
.peer_random
= new->peer
.peer_random
;
1300 new->peer
.peer_random
= NULL
;
1302 kfree(asoc
->peer
.peer_chunks
);
1303 asoc
->peer
.peer_chunks
= new->peer
.peer_chunks
;
1304 new->peer
.peer_chunks
= NULL
;
1306 kfree(asoc
->peer
.peer_hmacs
);
1307 asoc
->peer
.peer_hmacs
= new->peer
.peer_hmacs
;
1308 new->peer
.peer_hmacs
= NULL
;
1310 sctp_auth_key_put(asoc
->asoc_shared_key
);
1311 sctp_auth_asoc_init_active_key(asoc
, GFP_ATOMIC
);
1314 /* Update the retran path for sending a retransmitted packet.
1315 * Round-robin through the active transports, else round-robin
1316 * through the inactive transports as this is the next best thing
1319 void sctp_assoc_update_retran_path(struct sctp_association
*asoc
)
1321 struct sctp_transport
*t
, *next
;
1322 struct list_head
*head
= &asoc
->peer
.transport_addr_list
;
1323 struct list_head
*pos
;
1325 if (asoc
->peer
.transport_count
== 1)
1328 /* Find the next transport in a round-robin fashion. */
1329 t
= asoc
->peer
.retran_path
;
1330 pos
= &t
->transports
;
1334 /* Skip the head. */
1335 if (pos
->next
== head
)
1340 t
= list_entry(pos
, struct sctp_transport
, transports
);
1342 /* We have exhausted the list, but didn't find any
1343 * other active transports. If so, use the next
1346 if (t
== asoc
->peer
.retran_path
) {
1351 /* Try to find an active transport. */
1353 if ((t
->state
== SCTP_ACTIVE
) ||
1354 (t
->state
== SCTP_UNKNOWN
)) {
1357 /* Keep track of the next transport in case
1358 * we don't find any active transport.
1360 if (t
->state
!= SCTP_UNCONFIRMED
&& !next
)
1366 asoc
->peer
.retran_path
= t
;
1368 t
= asoc
->peer
.retran_path
;
1370 SCTP_DEBUG_PRINTK_IPADDR("sctp_assoc_update_retran_path:association"
1375 ntohs(t
->ipaddr
.v4
.sin_port
));
1378 /* Choose the transport for sending retransmit packet. */
1379 struct sctp_transport
*sctp_assoc_choose_alter_transport(
1380 struct sctp_association
*asoc
, struct sctp_transport
*last_sent_to
)
1382 /* If this is the first time packet is sent, use the active path,
1383 * else use the retran path. If the last packet was sent over the
1384 * retran path, update the retran path and use it.
1387 return asoc
->peer
.active_path
;
1389 if (last_sent_to
== asoc
->peer
.retran_path
)
1390 sctp_assoc_update_retran_path(asoc
);
1391 return asoc
->peer
.retran_path
;
1395 /* Update the association's pmtu and frag_point by going through all the
1396 * transports. This routine is called when a transport's PMTU has changed.
1398 void sctp_assoc_sync_pmtu(struct sock
*sk
, struct sctp_association
*asoc
)
1400 struct sctp_transport
*t
;
1406 /* Get the lowest pmtu of all the transports. */
1407 list_for_each_entry(t
, &asoc
->peer
.transport_addr_list
,
1409 if (t
->pmtu_pending
&& t
->dst
) {
1410 sctp_transport_update_pmtu(sk
, t
, dst_mtu(t
->dst
));
1411 t
->pmtu_pending
= 0;
1413 if (!pmtu
|| (t
->pathmtu
< pmtu
))
1418 asoc
->pathmtu
= pmtu
;
1419 asoc
->frag_point
= sctp_frag_point(asoc
, pmtu
);
1422 SCTP_DEBUG_PRINTK("%s: asoc:%p, pmtu:%d, frag_point:%d\n",
1423 __func__
, asoc
, asoc
->pathmtu
, asoc
->frag_point
);
1426 /* Should we send a SACK to update our peer? */
1427 static inline int sctp_peer_needs_update(struct sctp_association
*asoc
)
1429 struct net
*net
= sock_net(asoc
->base
.sk
);
1430 switch (asoc
->state
) {
1431 case SCTP_STATE_ESTABLISHED
:
1432 case SCTP_STATE_SHUTDOWN_PENDING
:
1433 case SCTP_STATE_SHUTDOWN_RECEIVED
:
1434 case SCTP_STATE_SHUTDOWN_SENT
:
1435 if ((asoc
->rwnd
> asoc
->a_rwnd
) &&
1436 ((asoc
->rwnd
- asoc
->a_rwnd
) >= max_t(__u32
,
1437 (asoc
->base
.sk
->sk_rcvbuf
>> net
->sctp
.rwnd_upd_shift
),
1447 /* Increase asoc's rwnd by len and send any window update SACK if needed. */
1448 void sctp_assoc_rwnd_increase(struct sctp_association
*asoc
, unsigned int len
)
1450 struct sctp_chunk
*sack
;
1451 struct timer_list
*timer
;
1453 if (asoc
->rwnd_over
) {
1454 if (asoc
->rwnd_over
>= len
) {
1455 asoc
->rwnd_over
-= len
;
1457 asoc
->rwnd
+= (len
- asoc
->rwnd_over
);
1458 asoc
->rwnd_over
= 0;
1464 /* If we had window pressure, start recovering it
1465 * once our rwnd had reached the accumulated pressure
1466 * threshold. The idea is to recover slowly, but up
1467 * to the initial advertised window.
1469 if (asoc
->rwnd_press
&& asoc
->rwnd
>= asoc
->rwnd_press
) {
1470 int change
= min(asoc
->pathmtu
, asoc
->rwnd_press
);
1471 asoc
->rwnd
+= change
;
1472 asoc
->rwnd_press
-= change
;
1475 SCTP_DEBUG_PRINTK("%s: asoc %p rwnd increased by %d to (%u, %u) "
1476 "- %u\n", __func__
, asoc
, len
, asoc
->rwnd
,
1477 asoc
->rwnd_over
, asoc
->a_rwnd
);
1479 /* Send a window update SACK if the rwnd has increased by at least the
1480 * minimum of the association's PMTU and half of the receive buffer.
1481 * The algorithm used is similar to the one described in
1482 * Section 4.2.3.3 of RFC 1122.
1484 if (sctp_peer_needs_update(asoc
)) {
1485 asoc
->a_rwnd
= asoc
->rwnd
;
1486 SCTP_DEBUG_PRINTK("%s: Sending window update SACK- asoc: %p "
1487 "rwnd: %u a_rwnd: %u\n", __func__
,
1488 asoc
, asoc
->rwnd
, asoc
->a_rwnd
);
1489 sack
= sctp_make_sack(asoc
);
1493 asoc
->peer
.sack_needed
= 0;
1495 sctp_outq_tail(&asoc
->outqueue
, sack
);
1497 /* Stop the SACK timer. */
1498 timer
= &asoc
->timers
[SCTP_EVENT_TIMEOUT_SACK
];
1499 if (del_timer(timer
))
1500 sctp_association_put(asoc
);
1504 /* Decrease asoc's rwnd by len. */
1505 void sctp_assoc_rwnd_decrease(struct sctp_association
*asoc
, unsigned int len
)
1510 SCTP_ASSERT(asoc
->rwnd
, "rwnd zero", return);
1511 SCTP_ASSERT(!asoc
->rwnd_over
, "rwnd_over not zero", return);
1513 if (asoc
->ep
->rcvbuf_policy
)
1514 rx_count
= atomic_read(&asoc
->rmem_alloc
);
1516 rx_count
= atomic_read(&asoc
->base
.sk
->sk_rmem_alloc
);
1518 /* If we've reached or overflowed our receive buffer, announce
1519 * a 0 rwnd if rwnd would still be positive. Store the
1520 * the pottential pressure overflow so that the window can be restored
1521 * back to original value.
1523 if (rx_count
>= asoc
->base
.sk
->sk_rcvbuf
)
1526 if (asoc
->rwnd
>= len
) {
1529 asoc
->rwnd_press
+= asoc
->rwnd
;
1533 asoc
->rwnd_over
= len
- asoc
->rwnd
;
1536 SCTP_DEBUG_PRINTK("%s: asoc %p rwnd decreased by %d to (%u, %u, %u)\n",
1537 __func__
, asoc
, len
, asoc
->rwnd
,
1538 asoc
->rwnd_over
, asoc
->rwnd_press
);
1541 /* Build the bind address list for the association based on info from the
1542 * local endpoint and the remote peer.
1544 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association
*asoc
,
1545 sctp_scope_t scope
, gfp_t gfp
)
1549 /* Use scoping rules to determine the subset of addresses from
1552 flags
= (PF_INET6
== asoc
->base
.sk
->sk_family
) ? SCTP_ADDR6_ALLOWED
: 0;
1553 if (asoc
->peer
.ipv4_address
)
1554 flags
|= SCTP_ADDR4_PEERSUPP
;
1555 if (asoc
->peer
.ipv6_address
)
1556 flags
|= SCTP_ADDR6_PEERSUPP
;
1558 return sctp_bind_addr_copy(sock_net(asoc
->base
.sk
),
1559 &asoc
->base
.bind_addr
,
1560 &asoc
->ep
->base
.bind_addr
,
1564 /* Build the association's bind address list from the cookie. */
1565 int sctp_assoc_set_bind_addr_from_cookie(struct sctp_association
*asoc
,
1566 struct sctp_cookie
*cookie
,
1569 int var_size2
= ntohs(cookie
->peer_init
->chunk_hdr
.length
);
1570 int var_size3
= cookie
->raw_addr_list_len
;
1571 __u8
*raw
= (__u8
*)cookie
->peer_init
+ var_size2
;
1573 return sctp_raw_to_bind_addrs(&asoc
->base
.bind_addr
, raw
, var_size3
,
1574 asoc
->ep
->base
.bind_addr
.port
, gfp
);
1577 /* Lookup laddr in the bind address list of an association. */
1578 int sctp_assoc_lookup_laddr(struct sctp_association
*asoc
,
1579 const union sctp_addr
*laddr
)
1583 if ((asoc
->base
.bind_addr
.port
== ntohs(laddr
->v4
.sin_port
)) &&
1584 sctp_bind_addr_match(&asoc
->base
.bind_addr
, laddr
,
1585 sctp_sk(asoc
->base
.sk
)))
1591 /* Set an association id for a given association */
1592 int sctp_assoc_set_id(struct sctp_association
*asoc
, gfp_t gfp
)
1594 bool preload
= gfp
& __GFP_WAIT
;
1597 /* If the id is already assigned, keep it. */
1603 spin_lock_bh(&sctp_assocs_id_lock
);
1604 /* 0 is not a valid id, idr_low is always >= 1 */
1605 ret
= idr_alloc(&sctp_assocs_id
, asoc
, idr_low
, 0, GFP_NOWAIT
);
1608 if (idr_low
== INT_MAX
)
1611 spin_unlock_bh(&sctp_assocs_id_lock
);
1617 asoc
->assoc_id
= (sctp_assoc_t
)ret
;
1621 /* Free the ASCONF queue */
1622 static void sctp_assoc_free_asconf_queue(struct sctp_association
*asoc
)
1624 struct sctp_chunk
*asconf
;
1625 struct sctp_chunk
*tmp
;
1627 list_for_each_entry_safe(asconf
, tmp
, &asoc
->addip_chunk_list
, list
) {
1628 list_del_init(&asconf
->list
);
1629 sctp_chunk_free(asconf
);
1633 /* Free asconf_ack cache */
1634 static void sctp_assoc_free_asconf_acks(struct sctp_association
*asoc
)
1636 struct sctp_chunk
*ack
;
1637 struct sctp_chunk
*tmp
;
1639 list_for_each_entry_safe(ack
, tmp
, &asoc
->asconf_ack_list
,
1641 list_del_init(&ack
->transmitted_list
);
1642 sctp_chunk_free(ack
);
1646 /* Clean up the ASCONF_ACK queue */
1647 void sctp_assoc_clean_asconf_ack_cache(const struct sctp_association
*asoc
)
1649 struct sctp_chunk
*ack
;
1650 struct sctp_chunk
*tmp
;
1652 /* We can remove all the entries from the queue up to
1653 * the "Peer-Sequence-Number".
1655 list_for_each_entry_safe(ack
, tmp
, &asoc
->asconf_ack_list
,
1657 if (ack
->subh
.addip_hdr
->serial
==
1658 htonl(asoc
->peer
.addip_serial
))
1661 list_del_init(&ack
->transmitted_list
);
1662 sctp_chunk_free(ack
);
1666 /* Find the ASCONF_ACK whose serial number matches ASCONF */
1667 struct sctp_chunk
*sctp_assoc_lookup_asconf_ack(
1668 const struct sctp_association
*asoc
,
1671 struct sctp_chunk
*ack
;
1673 /* Walk through the list of cached ASCONF-ACKs and find the
1674 * ack chunk whose serial number matches that of the request.
1676 list_for_each_entry(ack
, &asoc
->asconf_ack_list
, transmitted_list
) {
1677 if (ack
->subh
.addip_hdr
->serial
== serial
) {
1678 sctp_chunk_hold(ack
);
1686 void sctp_asconf_queue_teardown(struct sctp_association
*asoc
)
1688 /* Free any cached ASCONF_ACK chunk. */
1689 sctp_assoc_free_asconf_acks(asoc
);
1691 /* Free the ASCONF queue. */
1692 sctp_assoc_free_asconf_queue(asoc
);
1694 /* Free any cached ASCONF chunk. */
1695 if (asoc
->addip_last_asconf
)
1696 sctp_chunk_free(asoc
->addip_last_asconf
);